Malaysia Reports Vaccine Derived Polio VDPV1: Need to Switch to IPV and Stop OPV

Malaysia Reports Vaccine Derived Polio VDPV1: Need to Switch to IPV and Stop OPV

Dr KK Aggarwal

President CMAAO and HCFI

AP: KUALA LUMPUR - Malaysia began a vaccination campaign in a rural town on Borneo island after a 3-month-old boy was confirmed to have vaccine derived polio after 27 years.
               

The infant from Tuaran town in Sabah state tested positive for polio on Friday after he was hospitalized with fever and muscle weakness.

Poliovirus is classified as a circulating vaccine-derived poliovirus type 1 (VDPV1), which originates from a poliovirus that has been weakened by the orally-administered polio vaccine.

Vaccine-derived polioviruses (VDPV) are Sabin (OPV) virus derivatives that circulate in settings of low population immunity (eg, with low immunization rates) and revert to neurovirulence with ongoing transmission.

The emergence of VDPV requires that use of all OPV vaccines must cease in order to achieve the goal of global poliomyelitis eradication.

Malaysia is the second Asian country to have reported a vaccine derived polio case after an outbreak in the Philippines in September.

Tests showed the baby's strain had genetic links to the vaccine derived polio virus detected in Philippines.

The strain originated from a weakened virus contained in oral polio vaccine that was excreted from the body through feces and believed to have spread in an unsanitary environment to those who haven't been immunized.
              

Concerns

1.     Since 2005, approximately 80 percent of cases occurring during cVDPV outbreaks have been caused by type 2 OPV virus. The recognition of cVDPVs dictates that all OPV use will need to cease to achieve full polio eradication.

2.     This case is VDPV1

3.     Each use of OPV2 response to a VDPV2 outbreak carries a risk of seeding new VDPV2 outbreaks. Therefore, timely control of VDPV2 outbreaks in the context of a growing cohort of children who do not have immunity to type 2 poliovirus is critical to the success of polio eradication.

4.     The present immunisation should be IPV and not OPV

More inputs are invited